Occurrence of Aggregatibacter actinomycetemcomitans in Brazilians with chronic periodontitis

Abstract

Studies have suggested that A. actinomycetemcomitans is involved in the aetiology of aggressive periodontitis as well as in chronic periodontitis. This study was aimed at elucidating the occurrence of A. actinomycetemcomitans in a Brazilian population with chronic periodontitis. A total of 555 (mean age 33.04 ± 12.45) individuals, living in two large areas of the São Paulo State, namely "Baixada Santista" and "Vale do Paraíba", and diagnosed with mild [180 (mean age 29.59 ± 10.94)], moderate [241 (mean age 31.18 ± 11.45)] or severe [134 (mean age 33.04 ± 12.45)] chronic periodontitis were enrolled in this survey. Clinical exams including measurements of Probing Depth, Clinical Attachment Loss, Plaque and Gingival indices and subgingival microbiological assessments were performed at all population. The genomic DNA of A. actinomycetemcomitans was identified by Polymerase Chain Reaction from periodontal pocket samples. The occurrence of A. actinomycetemcomitans among chronic periodontitis subjects as well as its association with age and gender were statistically analysed using the Chi-square and Odds Ratio tests. The significance of differences was established at 5% (p < 0.05). A. actinomycetemcomitans was detected in 102 (18.37%) individuals: 29 (16.11%) mild; 42 (17.42%) moderate; and 31 (23.13%) severe chronic periodontitis with no statistical difference among groups. A higher occurrence of the searched bacterium was found both in the youngest group (p < 0.05) as well as in the female group (p < 0.05). This study elucidated that A. actinomycetemcomitans harbored subgingival pockets of our target group of chronic periodontitis subjects and that this bacterium seems to be inversely related to age, but related to the female gender.

Prevalence and distribution of Aggregatibacter actinomycetemcomitans and its cdtB gene in subgingival plaque of Chinese periodontitis patients

“…Some studies have examined the prevalence of A.actinomycetemcomitan s in some different populations [4,13,18]. Our work is the first report on the analysis of both positive rate and absolute quantity of A.actinomycetemcomitans and its cdt B gene in Chinese periodontitis patients, and the association of the distribution of A.actinomycetemcomitans and cdtB with various periodontal status.…”

“…Therefore, we chose different periodontal sites as targets to explore the occurrence and quantity of A.actinomycetemcomitans and its CDT encoding gene in Chinese subjects and different periodontal status. A.actinomycetemcomitans might not be present in all oral sites in an untreated periodontitis patient [18]. Taking subgingival samples from all teeth would be the most reliable way to detect A.actinomycetemcomitans .…”

“…However, this method is money- consuming and time-consuming which is not suitable to be used in daily practice. Sampling from the deepest pocket of each quadrant has been demonstrated to be quite reliable for detecting the subgingival presence of periodontal pathogens in untreated patients [18]. This technique was based on individual level.…”

Decreased phagocytic function in neutrophils and monocytes from peripheral blood in periodontal disease

“…Data support the microbial etiology of periodontal disease and the role played by specific pathogenic species 5,25 . Polymorphonuclear (PMN) neutrophils constitute the first line of defense against these pathogens in the subgingival area.…”

“…As our aim was to evaluate the effects of this interaction in the host, this justifies another stimulus provided to the cell, including yeasts. The use of different stimuli is reported in the literature: N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) 29 , Staphylococcus aureus 5 , Candida albicans 2,25 , Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis 13,21 .…”